86 ASM: ret program glitch

To: CALC-TI@LISTS.PPP.TI.COM
Subject: 86 ASM: ret program glitch
From: Joseph <johannas@geocities.com>
Date: Fri, 9 Jan 1998 23:52:15 -0500
Organization: none
Reply-To: johannas@geocities.com
Xref: paladin.american.edu bit.listserv.calc-ti:19680

I am having a problem with exiting a program. I'm using a GET_KEY
procedure (displayed at the end), which is most of the program. The ret
goes back to absolutely nothing, but the final ret. The call right
before this procedure is the last command in the main procedure. For
some reason, it doesn't exit until the second time I press EXIT. It
doesn't matter when I press exit the first or second times, the second
time I press exit, it quits, and not before. I could push exit, push
every other button, and then push exit again, and it would close. It
seems to still follow the GET_KEY proc after the first exit, which
shouldn't happen. It's returned out of it, right? What is going on??

MainLoop:
 call CheckForKey
 ret

CheckForKey:
  halt
  call GET_KEY
  cp K_1
  jp z,Ch1
  cp K_2
  jp z,Ch2
  cp K_3
  jp z,Ch3
  cp K_4
  jp z,Ch4
  cp K_5
  jp z,Ch5
  cp K_6
  jp z,Ch6
  cp K_7
  jp z,Ch7
  cp K_8
  jp z,Ch8
  cp K_9
  jp z,Ch9
  cp K_EXIT
  ret z
  cp 0
  jp z,CheckForKey